The present invention relates to a dispenser for dispensing portions of liquid or pasty products from a container.
Soap dispensers are for instance known for dispensing portions of liquid soap, and are mainly used in public wash-rooms, but they are especially unhygienic, since the contents are expelled by manual pressure on the mouthpiece of the apparatus. This construction is thus quite unsuitable for use in the washrooms of hospitals or the like.
Attempts have also been made to provide dispensers which are fitted with a double valve operable so that when a pressure was developed in a chamber housing the double valve closed with its upper half the through channel leading to the container on which the dispenser is fitted, its lower half opened this channel towards the exit pipe of the dispenser. These valve halves are however formed in a very disadvantageous manner as a mouthpiece, consisting for instance of flexible material, and conically tapering, the aperture consisting of a groove extending transversely across the cone surface. Since the lower half of the valve opens directly into the surrounding external air, an unavoidable oxidation of the liquid or pasty product takes place both at the mouthpiece and inside it. Consequently a plug forms in this half of the valve, and makes further operation of the dispenser impossible.